Building a Soft-Robot Tentacle

Designer Matthew Borgatti has debuted his nearly complete 3D-printed Trefoil Tentacle Soft Robot.  With the help of Viridis3D, Matthew printed a mold of his tentacle from a corn-starch-based material developed by Viridis3D called MakerDust. The outer shell of the mold was then reinforced with a two part resin, turning it into a rigid and durable structure.

While the design of the robot’s body is impressive, the way the beast moves really excited my geeky side. Unlike traditional robots that contain myriad moving parts, this little guy is controlled by pumping air through bladders along its body.

Matthew describes how he was able to control his robot on his site, “The control scheme is pretty simple: a barebones visual interface in processing sends signals to an Arduino. From there, it switches the low-power signal to high power via a Darlington transistor. The transistor switches each of three solenoid valves on and off, providing air to each of the three bladders inside of the silicone tentacle. The valves operate on a really slow PWM; their duty cycle determining how much air makes it to each bladder. Since there’s a bleed I can control on the system, I don’t have to worry about pumping air both in and out. I just adjust how much time the valves spend on, and the tentacle does it’s routine.”

If you’d like to take a step-by-step tour through the making of this incredible machine start here.

Awesome work Matthew!

Watch the Trefoil in Action Below:

Image and Video Courtesy of Matthew Borgatti